The tale of the last years of Heraclius is most melancholy. The Emperor lay at Constantinople slowly dying of dropsy, and his eldest son Constantine had to take the field in his stead. But the young prince received a crushing defeat in 638, when he attempted to recover North Syria, and next year the Arabs, under Amrou, pressed eastward across the Isthmus of Suez, and threw themselves upon Egypt. Two years more of fighting sufficed to conquer the granary of the Roman Empire; and in February, 641, when Heraclius died, the single port of Alexandria was the sole remaining possession of the Romans in Egypt. The ten years’ war which had torn Syria and Egypt from the hands of the unfortunate Heraclius had been even more fatal to his Eastern neighbour. The Arabs had attacked the Persian kingdom at the same moment that they fell on Syria: two great battles at Kadesia [636] and Yalulah [637] sufficed to place all Western Persia in the hands of the Moslems. King Isdigerd, the last of the Sassanian line, raised his last army in 641, and saw it cut to pieces at the decisive field of Nehauend. He fled away to dwell as an exile among the Turks, and all his kingdom as far as the borders of India became the prey of the conquerors. Heraclius had married twice; by his first wife, Eudocia, he left a single son, Constantine, who should have been his sole heir. But he had taken a second wife, and this wife was his own niece Martina. The incestuous choice had provoked much scandal, and was the one grave offence which could be brought against Heraclius, whose life was in other respects blameless. Martina, an ambitious and intriguing woman, prevailed on her aged husband to make her eldest son, Heracleonas, joint-heir with his half brother Constantine.